Weight loss supplements do not work, say experts

Two studies found that health supplements were no more effective than placebos

Slimming supplements are a waste of time and money and should be banned, experts said last night.

Despite claims that the boost metabolism, burn fat and blunt appetite, over-the-counter diet supplements are no more effective than dummy pills, research shows.

The finding will come as a blow to the hundreds of thousands of women who are relying on pills and potions based on everything from cabbage to chitosan, a sugar found in shellfish, to help them get their body ready the beach.

Researcher Thomas Ellrott said: 'There are scores of slimming supplements out there claiming weight-loss effects through all sorts of mechanisms of action.

'We have so-called fat magnets, mobilizers and dissolvers, as well as appetite tamers, metabolism boosters, carb blockers and so on. The market for these is huge, but unlike for regulated drugs, effectiveness does not have to be proven for these to be sold.

'Few of these supplements have been submitted to clinical trials and the landscape of products is always changing, so we need to put them through rigorous scientific evaluation to determine whether they have any benefit..'

Dr Ellrott, of the University of Gottingen Medical School in Germany, pitted nine popular slimming supplements against placebo pills, to see how well they worked.

They included cabbage powder, bean extracts, fibre pills and L-carnitine, a common constituent of many diet pills.

The men and women - who were unaware whether they had been given fake or real tablets - took them for eight weeks.

Although most lost a few pounds, those on placebo pills shed just as much weight as those on the slimming supplements, the International Congress on Obesity in Stockholm heard.

Dr Ellrott said that weight watchers would be better spending their cash on proven medications, such as orlistat, which goes under the brand names Xenical and Alli.

A separate review of previous studies into popular supplements also found them to be of no benefit.

Researcher Dr Igho Onakpoya of Peninsula Medical School at the Universities of Exeter and Plymouth, UK, said: 'In Western Europe, sales of weight-loss products, excluding prescription medications, topped £900 million in 2009.

'People think these supplements are a short cut to weight loss and may spend huge sums of money on them, but they may end up disappointed, frustrated and depressed if their weight expectations are not met in the long-term.'

Calling for slimming supplements to be banned, Professor Judith Stern, of the University of California, Davis, said: 'The only thing you will lose is your money.'

Victoria Taylor, senior heart health dietician at the British Heart Foundation, said: "There are no quick fixes when it comes to weight loss.

'To reduce weight we need to be using up more energy than we are taking in and to achieve this we have to make changes to what we eat and how much activity we do.

'A huge amount of money is spent on the dieting industry, but it's often money down the drain.

'Small, sustainable changes to diet and physical activity are likely to be the most effective approach to keeping weight off in the long term - and it needn't cost you a penny.'